// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (c) International Business Machines Corp., 2006 * Copyright (c) Nokia Corporation, 2007 * * Author: Artem Bityutskiy (Битюцкий Артём), * Frank Haverkamp */ /* * This file includes UBI initialization and building of UBI devices. * * When UBI is initialized, it attaches all the MTD devices specified as the * module load parameters or the kernel boot parameters. If MTD devices were * specified, UBI does not attach any MTD device, but it is possible to do * later using the "UBI control device". */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ubi.h" /* Maximum length of the 'mtd=' parameter */ #define MTD_PARAM_LEN_MAX 64 /* Maximum number of comma-separated items in the 'mtd=' parameter */ #define MTD_PARAM_MAX_COUNT 4 /* Maximum value for the number of bad PEBs per 1024 PEBs */ #define MAX_MTD_UBI_BEB_LIMIT 768 #ifdef CONFIG_MTD_UBI_MODULE #define ubi_is_module() 1 #else #define ubi_is_module() 0 #endif /** * struct mtd_dev_param - MTD device parameter description data structure. * @name: MTD character device node path, MTD device name, or MTD device number * string * @ubi_num: UBI number * @vid_hdr_offs: VID header offset * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs */ struct mtd_dev_param { char name[MTD_PARAM_LEN_MAX]; int ubi_num; int vid_hdr_offs; int max_beb_per1024; }; /* Numbers of elements set in the @mtd_dev_param array */ static int mtd_devs; /* MTD devices specification parameters */ static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES]; #ifdef CONFIG_MTD_UBI_FASTMAP /* UBI module parameter to enable fastmap automatically on non-fastmap images */ static bool fm_autoconvert; static bool fm_debug; #endif /* Slab cache for wear-leveling entries */ struct kmem_cache *ubi_wl_entry_slab; /* UBI control character device */ static struct miscdevice ubi_ctrl_cdev = { .minor = MISC_DYNAMIC_MINOR, .name = "ubi_ctrl", .fops = &ubi_ctrl_cdev_operations, }; /* All UBI devices in system */ static struct ubi_device *ubi_devices[UBI_MAX_DEVICES]; /* Serializes UBI devices creations and removals */ DEFINE_MUTEX(ubi_devices_mutex); /* Protects @ubi_devices and @ubi->ref_count */ static DEFINE_SPINLOCK(ubi_devices_lock); /* "Show" method for files in '//class/ubi/' */ /* UBI version attribute ('//class/ubi/version') */ static ssize_t version_show(struct class *class, struct class_attribute *attr, char *buf) { return sprintf(buf, "%d\n", UBI_VERSION); } static CLASS_ATTR_RO(version); static struct attribute *ubi_class_attrs[] = { &class_attr_version.attr, NULL, }; ATTRIBUTE_GROUPS(ubi_class); /* Root UBI "class" object (corresponds to '//class/ubi/') */ struct class ubi_class = { .name = UBI_NAME_STR, .owner = THIS_MODULE, .class_groups = ubi_class_groups, }; static ssize_t dev_attribute_show(struct device *dev, struct device_attribute *attr, char *buf); /* UBI device attributes (correspond to files in '//class/ubi/ubiX') */ static struct device_attribute dev_eraseblock_size = __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_avail_eraseblocks = __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_total_eraseblocks = __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_volumes_count = __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_max_ec = __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_reserved_for_bad = __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_bad_peb_count = __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_max_vol_count = __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_min_io_size = __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_bgt_enabled = __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_mtd_num = __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_ro_mode = __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL); /** * ubi_volume_notify - send a volume change notification. * @ubi: UBI device description object * @vol: volume description object of the changed volume * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc) * * This is a helper function which notifies all subscribers about a volume * change event (creation, removal, re-sizing, re-naming, updating). Returns * zero in case of success and a negative error code in case of failure. */ int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype) { int ret; struct ubi_notification nt; ubi_do_get_device_info(ubi, &nt.di); ubi_do_get_volume_info(ubi, vol, &nt.vi); switch (ntype) { case UBI_VOLUME_ADDED: case UBI_VOLUME_REMOVED: case UBI_VOLUME_RESIZED: case UBI_VOLUME_RENAMED: ret = ubi_update_fastmap(ubi); if (ret) ubi_msg(ubi, "Unable to write a new fastmap: %i", ret); } return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt); } /** * ubi_notify_all - send a notification to all volumes. * @ubi: UBI device description object * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc) * @nb: the notifier to call * * This function walks all volumes of UBI device @ubi and sends the @ntype * notification for each volume. If @nb is %NULL, then all registered notifiers * are called, otherwise only the @nb notifier is called. Returns the number of * sent notifications. */ int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb) { struct ubi_notification nt; int i, count = 0; ubi_do_get_device_info(ubi, &nt.di); mutex_lock(&ubi->device_mutex); for (i = 0; i < ubi->vtbl_slots; i++) { /* * Since the @ubi->device is locked, and we are not going to * change @ubi->volumes, we do not have to lock * @ubi->volumes_lock. */ if (!ubi->volumes[i]) continue; ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi); if (nb) nb->notifier_call(nb, ntype, &nt); else blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt); count += 1; } mutex_unlock(&ubi->device_mutex); return count; } /** * ubi_enumerate_volumes - send "add" notification for all existing volumes. * @nb: the notifier to call * * This function walks all UBI devices and volumes and sends the * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all * registered notifiers are called, otherwise only the @nb notifier is called. * Returns the number of sent notifications. */ int ubi_enumerate_volumes(struct notifier_block *nb) { int i, count = 0; /* * Since the @ubi_devices_mutex is locked, and we are not going to * change @ubi_devices, we do not have to lock @ubi_devices_lock. */ for (i = 0; i < UBI_MAX_DEVICES; i++) { struct ubi_device *ubi = ubi_devices[i]; if (!ubi) continue; count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb); } return count; } /** * ubi_get_device - get UBI device. * @ubi_num: UBI device number * * This function returns UBI device description object for UBI device number * @ubi_num, or %NULL if the device does not exist. This function increases the * device reference count to prevent removal of the device. In other words, the * device cannot be removed if its reference count is not zero. */ struct ubi_device *ubi_get_device(int ubi_num) { struct ubi_device *ubi; spin_lock(&ubi_devices_lock); ubi = ubi_devices[ubi_num]; if (ubi) { ubi_assert(ubi->ref_count >= 0); ubi->ref_count += 1; get_device(&ubi->dev); } spin_unlock(&ubi_devices_lock); return ubi; } /** * ubi_put_device - drop an UBI device reference. * @ubi: UBI device description object */ void ubi_put_device(struct ubi_device *ubi) { spin_lock(&ubi_devices_lock); ubi->ref_count -= 1; put_device(&ubi->dev); spin_unlock(&ubi_devices_lock); } /** * ubi_get_by_major - get UBI device by character device major number. * @major: major number * * This function is similar to 'ubi_get_device()', but it searches the device * by its major number. */ struct ubi_device *ubi_get_by_major(int major) { int i; struct ubi_device *ubi; spin_lock(&ubi_devices_lock); for (i = 0; i < UBI_MAX_DEVICES; i++) { ubi = ubi_devices[i]; if (ubi && MAJOR(ubi->cdev.dev) == major) { ubi_assert(ubi->ref_count >= 0); ubi->ref_count += 1; get_device(&ubi->dev); spin_unlock(&ubi_devices_lock); return ubi; } } spin_unlock(&ubi_devices_lock); return NULL; } /** * ubi_major2num - get UBI device number by character device major number. * @major: major number * * This function searches UBI device number object by its major number. If UBI * device was not found, this function returns -ENODEV, otherwise the UBI device * number is returned. */ int ubi_major2num(int major) { int i, ubi_num = -ENODEV; spin_lock(&ubi_devices_lock); for (i = 0; i < UBI_MAX_DEVICES; i++) { struct ubi_device *ubi = ubi_devices[i]; if (ubi && MAJOR(ubi->cdev.dev) == major) { ubi_num = ubi->ubi_num; break; } } spin_unlock(&ubi_devices_lock); return ubi_num; } /* "Show" method for files in '//class/ubi/ubiX/' */ static ssize_t dev_attribute_show(struct device *dev, struct device_attribute *attr, char *buf) { ssize_t ret; struct ubi_device *ubi; /* * The below code looks weird, but it actually makes sense. We get the * UBI device reference from the contained 'struct ubi_device'. But it * is unclear if the device was removed or not yet. Indeed, if the * device was removed before we increased its reference count, * 'ubi_get_device()' will return -ENODEV and we fail. * * Remember, 'struct ubi_device' is freed in the release function, so * we still can use 'ubi->ubi_num'. */ ubi = container_of(dev, struct ubi_device, dev); if (attr == &dev_eraseblock_size) ret = sprintf(buf, "%d\n", ubi->leb_size); else if (attr == &dev_avail_eraseblocks) ret = sprintf(buf, "%d\n", ubi->avail_pebs); else if (attr == &dev_total_eraseblocks) ret = sprintf(buf, "%d\n", ubi->good_peb_count); else if (attr == &dev_volumes_count) ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT); else if (attr == &dev_max_ec) ret = sprintf(buf, "%d\n", ubi->max_ec); else if (attr == &dev_reserved_for_bad) ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs); else if (attr == &dev_bad_peb_count) ret = sprintf(buf, "%d\n", ubi->bad_peb_count); else if (attr == &dev_max_vol_count) ret = sprintf(buf, "%d\n", ubi->vtbl_slots); else if (attr == &dev_min_io_size) ret = sprintf(buf, "%d\n", ubi->min_io_size); else if (attr == &dev_bgt_enabled) ret = sprintf(buf, "%d\n", ubi->thread_enabled); else if (attr == &dev_mtd_num) ret = sprintf(buf, "%d\n", ubi->mtd->index); else if (attr == &dev_ro_mode) ret = sprintf(buf, "%d\n", ubi->ro_mode); else ret = -EINVAL; return ret; } static struct attribute *ubi_dev_attrs[] = { &dev_eraseblock_size.attr, &dev_avail_eraseblocks.attr, &dev_total_eraseblocks.attr, &dev_volumes_count.attr, &dev_max_ec.attr, &dev_reserved_for_bad.attr, &dev_bad_peb_count.attr, &dev_max_vol_count.attr, &dev_min_io_size.attr, &dev_bgt_enabled.attr, &dev_mtd_num.attr, &dev_ro_mode.attr, NULL }; ATTRIBUTE_GROUPS(ubi_dev); static void dev_release(struct device *dev) { struct ubi_device *ubi = container_of(dev, struct ubi_device, dev); kfree(ubi); } /** * kill_volumes - destroy all user volumes. * @ubi: UBI device description object */ static void kill_volumes(struct ubi_device *ubi) { int i; for (i = 0; i < ubi->vtbl_slots; i++) if (ubi->volumes[i]) ubi_free_volume(ubi, ubi->volumes[i]); } /** * uif_init - initialize user interfaces for an UBI device. * @ubi: UBI device description object * * This function initializes various user interfaces for an UBI device. If the * initialization fails at an early stage, this function frees all the * resources it allocated, returns an error. * * This function returns zero in case of success and a negative error code in * case of failure. */ static int uif_init(struct ubi_device *ubi) { int i, err; dev_t dev; sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num); /* * Major numbers for the UBI character devices are allocated * dynamically. Major numbers of volume character devices are * equivalent to ones of the corresponding UBI character device. Minor * numbers of UBI character devices are 0, while minor numbers of * volume character devices start from 1. Thus, we allocate one major * number and ubi->vtbl_slots + 1 minor numbers. */ err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name); if (err) { ubi_err(ubi, "cannot register UBI character devices"); return err; } ubi->dev.devt = dev; ubi_assert(MINOR(dev) == 0); cdev_init(&ubi->cdev, &ubi_cdev_operations); dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev)); ubi->cdev.owner = THIS_MODULE; dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num); err = cdev_device_add(&ubi->cdev, &ubi->dev); if (err) goto out_unreg; for (i = 0; i < ubi->vtbl_slots; i++) if (ubi->volumes[i]) { err = ubi_add_volume(ubi, ubi->volumes[i]); if (err) { ubi_err(ubi, "cannot add volume %d", i); ubi->volumes[i] = NULL; goto out_volumes; } } return 0; out_volumes: kill_volumes(ubi); cdev_device_del(&ubi->cdev, &ubi->dev); out_unreg: unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1); ubi_err(ubi, "cannot initialize UBI %s, error %d", ubi->ubi_name, err); return err; } /** * uif_close - close user interfaces for an UBI device. * @ubi: UBI device description object * * Note, since this function un-registers UBI volume device objects (@vol->dev), * the memory allocated voe the volumes is freed as well (in the release * function). */ static void uif_close(struct ubi_device *ubi) { kill_volumes(ubi); cdev_device_del(&ubi->cdev, &ubi->dev); unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1); } /** * ubi_free_volumes_from - free volumes from specific index. * @ubi: UBI device description object * @from: the start index used for volume free. */ static void ubi_free_volumes_from(struct ubi_device *ubi, int from) { int i; for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { if (!ubi->volumes[i]) continue; ubi_eba_replace_table(ubi->volumes[i], NULL); ubi_fastmap_destroy_checkmap(ubi->volumes[i]); kfree(ubi->volumes[i]); ubi->volumes[i] = NULL; } } /** * ubi_free_all_volumes - free all volumes. * @ubi: UBI device description object */ void ubi_free_all_volumes(struct ubi_device *ubi) { ubi_free_volumes_from(ubi, 0); } /** * ubi_free_internal_volumes - free internal volumes. * @ubi: UBI device description object */ void ubi_free_internal_volumes(struct ubi_device *ubi) { ubi_free_volumes_from(ubi, ubi->vtbl_slots); } static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024) { int limit, device_pebs; uint64_t device_size; if (!max_beb_per1024) { /* * Since max_beb_per1024 has not been set by the user in either * the cmdline or Kconfig, use mtd_max_bad_blocks to set the * limit if it is supported by the device. */ limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size); if (limit < 0) return 0; return limit; } /* * Here we are using size of the entire flash chip and * not just the MTD partition size because the maximum * number of bad eraseblocks is a percentage of the * whole device and bad eraseblocks are not fairly * distributed over the flash chip. So the worst case * is that all the bad eraseblocks of the chip are in * the MTD partition we are attaching (ubi->mtd). */ device_size = mtd_get_device_size(ubi->mtd); device_pebs = mtd_div_by_eb(device_size, ubi->mtd); limit = mult_frac(device_pebs, max_beb_per1024, 1024); /* Round it up */ if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs) limit += 1; return limit; } /** * io_init - initialize I/O sub-system for a given UBI device. * @ubi: UBI device description object * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs * * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are * assumed: * o EC header is always at offset zero - this cannot be changed; * o VID header starts just after the EC header at the closest address * aligned to @io->hdrs_min_io_size; * o data starts just after the VID header at the closest address aligned to * @io->min_io_size * * This function returns zero in case of success and a negative error code in * case of failure. */ static int io_init(struct ubi_device *ubi, int max_beb_per1024) { dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb)); dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry)); if (ubi->mtd->numeraseregions != 0) { /* * Some flashes have several erase regions. Different regions * may have different eraseblock size and other * characteristics. It looks like mostly multi-region flashes * have one "main" region and one or more small regions to * store boot loader code or boot parameters or whatever. I * guess we should just pick the largest region. But this is * not implemented. */ ubi_err(ubi, "multiple regions, not implemented"); return -EINVAL; } if (ubi->vid_hdr_offset < 0) return -EINVAL; /* * Note, in this implementation we support MTD devices with 0x7FFFFFFF * physical eraseblocks maximum. */ ubi->peb_size = ubi->mtd->erasesize; ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd); ubi->flash_size = ubi->mtd->size; if (mtd_can_have_bb(ubi->mtd)) { ubi->bad_allowed = 1; ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024); } if (ubi->mtd->type == MTD_NORFLASH) ubi->nor_flash = 1; ubi->min_io_size = ubi->mtd->writesize; ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft; /* * Make sure minimal I/O unit is power of 2. Note, there is no * fundamental reason for this assumption. It is just an optimization * which allows us to avoid costly division operations. */ if (!is_power_of_2(ubi->min_io_size)) { ubi_err(ubi, "min. I/O unit (%d) is not power of 2", ubi->min_io_size); return -EINVAL; } ubi_assert(ubi->hdrs_min_io_size > 0); ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size); ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0); ubi->max_write_size = ubi->mtd->writebufsize; /* * Maximum write size has to be greater or equivalent to min. I/O * size, and be multiple of min. I/O size. */ if (ubi->max_write_size < ubi->min_io_size || ubi->max_write_size % ubi->min_io_size || !is_power_of_2(ubi->max_write_size)) { ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit", ubi->max_write_size, ubi->min_io_size); return -EINVAL; } /* Calculate default aligned sizes of EC and VID headers */ ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size); ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size); dbg_gen("min_io_size %d", ubi->min_io_size); dbg_gen("max_write_size %d", ubi->max_write_size); dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size); dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize); dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize); if (ubi->vid_hdr_offset == 0) /* Default offset */ ubi->vid_hdr_offset = ubi->vid_hdr_aloffset = ubi->ec_hdr_alsize; else { ubi->vid_hdr_aloffset = ubi->vid_hdr_offset & ~(ubi->hdrs_min_io_size - 1); ubi->vid_hdr_shift = ubi->vid_hdr_offset - ubi->vid_hdr_aloffset; } /* * Memory allocation for VID header is ubi->vid_hdr_alsize * which is described in comments in io.c. * Make sure VID header shift + UBI_VID_HDR_SIZE not exceeds * ubi->vid_hdr_alsize, so that all vid header operations * won't access memory out of bounds. */ if ((ubi->vid_hdr_shift + UBI_VID_HDR_SIZE) > ubi->vid_hdr_alsize) { ubi_err(ubi, "Invalid VID header offset %d, VID header shift(%d)" " + VID header size(%zu) > VID header aligned size(%d).", ubi->vid_hdr_offset, ubi->vid_hdr_shift, UBI_VID_HDR_SIZE, ubi->vid_hdr_alsize); return -EINVAL; } /* Similar for the data offset */ ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE; ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size); dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset); dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset); dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift); dbg_gen("leb_start %d", ubi->leb_start); /* The shift must be aligned to 32-bit boundary */ if (ubi->vid_hdr_shift % 4) { ubi_err(ubi, "unaligned VID header shift %d", ubi->vid_hdr_shift); return -EINVAL; } /* Check sanity */ if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE || ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE || ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE || ubi->leb_start & (ubi->min_io_size - 1)) { ubi_err(ubi, "bad VID header (%d) or data offsets (%d)", ubi->vid_hdr_offset, ubi->leb_start); return -EINVAL; } /* * Set maximum amount of physical erroneous eraseblocks to be 10%. * Erroneous PEB are those which have read errors. */ ubi->max_erroneous = ubi->peb_count / 10; if (ubi->max_erroneous < 16) ubi->max_erroneous = 16; dbg_gen("max_erroneous %d", ubi->max_erroneous); /* * It may happen that EC and VID headers are situated in one minimal * I/O unit. In this case we can only accept this UBI image in * read-only mode. */ if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) { ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode"); ubi->ro_mode = 1; } ubi->leb_size = ubi->peb_size - ubi->leb_start; if (!(ubi->mtd->flags & MTD_WRITEABLE)) { ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode", ubi->mtd->index); ubi->ro_mode = 1; } /* * Note, ideally, we have to initialize @ubi->bad_peb_count here. But * unfortunately, MTD does not provide this information. We should loop * over all physical eraseblocks and invoke mtd->block_is_bad() for * each physical eraseblock. So, we leave @ubi->bad_peb_count * uninitialized so far. */ return 0; } /** * autoresize - re-size the volume which has the "auto-resize" flag set. * @ubi: UBI device description object * @vol_id: ID of the volume to re-size * * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in * the volume table to the largest possible size. See comments in ubi-header.h * for more description of the flag. Returns zero in case of success and a * negative error code in case of failure. */ static int autoresize(struct ubi_device *ubi, int vol_id) { struct ubi_volume_desc desc; struct ubi_volume *vol = ubi->volumes[vol_id]; int err, old_reserved_pebs = vol->reserved_pebs; if (ubi->ro_mode) { ubi_warn(ubi, "skip auto-resize because of R/O mode"); return 0; } /* * Clear the auto-resize flag in the volume in-memory copy of the * volume table, and 'ubi_resize_volume()' will propagate this change * to the flash. */ ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG; if (ubi->avail_pebs == 0) { struct ubi_vtbl_record vtbl_rec; /* * No available PEBs to re-size the volume, clear the flag on * flash and exit. */ vtbl_rec = ubi->vtbl[vol_id]; err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); if (err) ubi_err(ubi, "cannot clean auto-resize flag for volume %d", vol_id); } else { desc.vol = vol; err = ubi_resize_volume(&desc, old_reserved_pebs + ubi->avail_pebs); if (err) ubi_err(ubi, "cannot auto-resize volume %d", vol_id); } if (err) return err; ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs); return 0; } /** * ubi_attach_mtd_dev - attach an MTD device. * @mtd: MTD device description object * @ubi_num: number to assign to the new UBI device * @vid_hdr_offset: VID header offset * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs * * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in * which case this function finds a vacant device number and assigns it * automatically. Returns the new UBI device number in case of success and a * negative error code in case of failure. * * Note, the invocations of this function has to be serialized by the * @ubi_devices_mutex. */ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset, int max_beb_per1024) { struct ubi_device *ubi; int i, err; if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT) return -EINVAL; if (!max_beb_per1024) max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT; /* * Check if we already have the same MTD device attached. * * Note, this function assumes that UBI devices creations and deletions * are serialized, so it does not take the &ubi_devices_lock. */ for (i = 0; i < UBI_MAX_DEVICES; i++) { ubi = ubi_devices[i]; if (ubi && mtd->index == ubi->mtd->index) { pr_err("ubi: mtd%d is already attached to ubi%d\n", mtd->index, i); return -EEXIST; } } /* * Make sure this MTD device is not emulated on top of an UBI volume * already. Well, generally this recursion works fine, but there are * different problems like the UBI module takes a reference to itself * by attaching (and thus, opening) the emulated MTD device. This * results in inability to unload the module. And in general it makes * no sense to attach emulated MTD devices, so we prohibit this. */ if (mtd->type == MTD_UBIVOLUME) { pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n", mtd->index); return -EINVAL; } /* * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes. * MLC NAND is different and needs special care, otherwise UBI or UBIFS * will die soon and you will lose all your data. * Relax this rule if the partition we're attaching to operates in SLC * mode. */ if (mtd->type == MTD_MLCNANDFLASH && !(mtd->flags & MTD_SLC_ON_MLC_EMULATION)) { pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n", mtd->index); return -EINVAL; } /* UBI cannot work on flashes with zero erasesize. */ if (!mtd->erasesize) { pr_err("ubi: refuse attaching mtd%d - zero erasesize flash is not supported\n", mtd->index); return -EINVAL; } if (ubi_num == UBI_DEV_NUM_AUTO) { /* Search for an empty slot in the @ubi_devices array */ for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++) if (!ubi_devices[ubi_num]) break; if (ubi_num == UBI_MAX_DEVICES) { pr_err("ubi: only %d UBI devices may be created\n", UBI_MAX_DEVICES); return -ENFILE; } } else { if (ubi_num >= UBI_MAX_DEVICES) return -EINVAL; /* Make sure ubi_num is not busy */ if (ubi_devices[ubi_num]) { pr_err("ubi: ubi%i already exists\n", ubi_num); return -EEXIST; } } ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL); if (!ubi) return -ENOMEM; device_initialize(&ubi->dev); ubi->dev.release = dev_release; ubi->dev.class = &ubi_class; ubi->dev.groups = ubi_dev_groups; ubi->mtd = mtd; ubi->ubi_num = ubi_num; ubi->vid_hdr_offset = vid_hdr_offset; ubi->autoresize_vol_id = -1; #ifdef CONFIG_MTD_UBI_FASTMAP ubi->fm_pool.used = ubi->fm_pool.size = 0; ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0; /* * fm_pool.max_size is 5% of the total number of PEBs but it's also * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE. */ ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE); ubi->fm_pool.max_size = max(ubi->fm_pool.max_size, UBI_FM_MIN_POOL_SIZE); ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2; ubi->fm_disabled = !fm_autoconvert; if (fm_debug) ubi_enable_dbg_chk_fastmap(ubi); if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) { ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.", UBI_FM_MAX_START); ubi->fm_disabled = 1; } ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size); ubi_msg(ubi, "default fastmap WL pool size: %d", ubi->fm_wl_pool.max_size); #else ubi->fm_disabled = 1; #endif mutex_init(&ubi->buf_mutex); mutex_init(&ubi->ckvol_mutex); mutex_init(&ubi->device_mutex); spin_lock_init(&ubi->volumes_lock); init_rwsem(&ubi->fm_protect); init_rwsem(&ubi->fm_eba_sem); ubi_msg(ubi, "attaching mtd%d", mtd->index); err = io_init(ubi, max_beb_per1024); if (err) goto out_free; err = -ENOMEM; ubi->peb_buf = vmalloc(ubi->peb_size); if (!ubi->peb_buf) goto out_free; #ifdef CONFIG_MTD_UBI_FASTMAP ubi->fm_size = ubi_calc_fm_size(ubi); ubi->fm_buf = vzalloc(ubi->fm_size); if (!ubi->fm_buf) goto out_free; #endif err = ubi_attach(ubi, 0); if (err) { ubi_err(ubi, "failed to attach mtd%d, error %d", mtd->index, err); goto out_free; } if (ubi->autoresize_vol_id != -1) { err = autoresize(ubi, ubi->autoresize_vol_id); if (err) goto out_detach; } err = uif_init(ubi); if (err) goto out_detach; err = ubi_debugfs_init_dev(ubi); if (err) goto out_uif; ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name); if (IS_ERR(ubi->bgt_thread)) { err = PTR_ERR(ubi->bgt_thread); ubi_err(ubi, "cannot spawn \"%s\", error %d", ubi->bgt_name, err); goto out_debugfs; } ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)", mtd->index, mtd->name, ubi->flash_size >> 20); ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes", ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size); ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d", ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size); ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d", ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start); ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d", ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count); ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d", ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT, ubi->vtbl_slots); ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u", ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD, ubi->image_seq); ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d", ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs); /* * The below lock makes sure we do not race with 'ubi_thread()' which * checks @ubi->thread_enabled. Otherwise we may fail to wake it up. */ spin_lock(&ubi->wl_lock); ubi->thread_enabled = 1; wake_up_process(ubi->bgt_thread); spin_unlock(&ubi->wl_lock); ubi_devices[ubi_num] = ubi; ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL); return ubi_num; out_debugfs: ubi_debugfs_exit_dev(ubi); out_uif: uif_close(ubi); out_detach: ubi_wl_close(ubi); ubi_free_all_volumes(ubi); vfree(ubi->vtbl); out_free: vfree(ubi->peb_buf); vfree(ubi->fm_buf); put_device(&ubi->dev); return err; } /** * ubi_detach_mtd_dev - detach an MTD device. * @ubi_num: UBI device number to detach from * @anyway: detach MTD even if device reference count is not zero * * This function destroys an UBI device number @ubi_num and detaches the * underlying MTD device. Returns zero in case of success and %-EBUSY if the * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not * exist. * * Note, the invocations of this function has to be serialized by the * @ubi_devices_mutex. */ int ubi_detach_mtd_dev(int ubi_num, int anyway) { struct ubi_device *ubi; if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) return -EINVAL; ubi = ubi_get_device(ubi_num); if (!ubi) return -EINVAL; spin_lock(&ubi_devices_lock); put_device(&ubi->dev); ubi->ref_count -= 1; if (ubi->ref_count) { if (!anyway) { spin_unlock(&ubi_devices_lock); return -EBUSY; } /* This may only happen if there is a bug */ ubi_err(ubi, "%s reference count %d, destroy anyway", ubi->ubi_name, ubi->ref_count); } ubi_devices[ubi_num] = NULL; spin_unlock(&ubi_devices_lock); ubi_assert(ubi_num == ubi->ubi_num); ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL); ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index); #ifdef CONFIG_MTD_UBI_FASTMAP /* If we don't write a new fastmap at detach time we lose all * EC updates that have been made since the last written fastmap. * In case of fastmap debugging we omit the update to simulate an * unclean shutdown. */ if (!ubi_dbg_chk_fastmap(ubi)) ubi_update_fastmap(ubi); #endif /* * Before freeing anything, we have to stop the background thread to * prevent it from doing anything on this device while we are freeing. */ if (ubi->bgt_thread) kthread_stop(ubi->bgt_thread); #ifdef CONFIG_MTD_UBI_FASTMAP cancel_work_sync(&ubi->fm_work); #endif ubi_debugfs_exit_dev(ubi); uif_close(ubi); ubi_wl_close(ubi); ubi_free_internal_volumes(ubi); vfree(ubi->vtbl); vfree(ubi->peb_buf); vfree(ubi->fm_buf); ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index); put_mtd_device(ubi->mtd); put_device(&ubi->dev); return 0; } /** * open_mtd_by_chdev - open an MTD device by its character device node path. * @mtd_dev: MTD character device node path * * This helper function opens an MTD device by its character node device path. * Returns MTD device description object in case of success and a negative * error code in case of failure. */ static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev) { int err, minor; struct path path; struct kstat stat; /* Probably this is an MTD character device node path */ err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path); if (err) return ERR_PTR(err); err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); path_put(&path); if (err) return ERR_PTR(err); /* MTD device number is defined by the major / minor numbers */ if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode)) return ERR_PTR(-EINVAL); minor = MINOR(stat.rdev); if (minor & 1) /* * Just do not think the "/dev/mtdrX" devices support is need, * so do not support them to avoid doing extra work. */ return ERR_PTR(-EINVAL); return get_mtd_device(NULL, minor / 2); } /** * open_mtd_device - open MTD device by name, character device path, or number. * @mtd_dev: name, character device node path, or MTD device device number * * This function tries to open and MTD device described by @mtd_dev string, * which is first treated as ASCII MTD device number, and if it is not true, it * is treated as MTD device name, and if that is also not true, it is treated * as MTD character device node path. Returns MTD device description object in * case of success and a negative error code in case of failure. */ static struct mtd_info * __init open_mtd_device(const char *mtd_dev) { struct mtd_info *mtd; int mtd_num; char *endp; mtd_num = simple_strtoul(mtd_dev, &endp, 0); if (*endp != '\0' || mtd_dev == endp) { /* * This does not look like an ASCII integer, probably this is * MTD device name. */ mtd = get_mtd_device_nm(mtd_dev); if (PTR_ERR(mtd) == -ENODEV) /* Probably this is an MTD character device node path */ mtd = open_mtd_by_chdev(mtd_dev); } else mtd = get_mtd_device(NULL, mtd_num); return mtd; } static int __init ubi_init(void) { int err, i, k; /* Ensure that EC and VID headers have correct size */ BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64); BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64); if (mtd_devs > UBI_MAX_DEVICES) { pr_err("UBI error: too many MTD devices, maximum is %d\n", UBI_MAX_DEVICES); return -EINVAL; } /* Create base sysfs directory and sysfs files */ err = class_register(&ubi_class); if (err < 0) return err; err = misc_register(&ubi_ctrl_cdev); if (err) { pr_err("UBI error: cannot register device\n"); goto out; } ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab", sizeof(struct ubi_wl_entry), 0, 0, NULL); if (!ubi_wl_entry_slab) { err = -ENOMEM; goto out_dev_unreg; } err = ubi_debugfs_init(); if (err) goto out_slab; /* Attach MTD devices */ for (i = 0; i < mtd_devs; i++) { struct mtd_dev_param *p = &mtd_dev_param[i]; struct mtd_info *mtd; cond_resched(); mtd = open_mtd_device(p->name); if (IS_ERR(mtd)) { err = PTR_ERR(mtd); pr_err("UBI error: cannot open mtd %s, error %d\n", p->name, err); /* See comment below re-ubi_is_module(). */ if (ubi_is_module()) goto out_detach; continue; } mutex_lock(&ubi_devices_mutex); err = ubi_attach_mtd_dev(mtd, p->ubi_num, p->vid_hdr_offs, p->max_beb_per1024); mutex_unlock(&ubi_devices_mutex); if (err < 0) { pr_err("UBI error: cannot attach mtd%d\n", mtd->index); put_mtd_device(mtd); /* * Originally UBI stopped initializing on any error. * However, later on it was found out that this * behavior is not very good when UBI is compiled into * the kernel and the MTD devices to attach are passed * through the command line. Indeed, UBI failure * stopped whole boot sequence. * * To fix this, we changed the behavior for the * non-module case, but preserved the old behavior for * the module case, just for compatibility. This is a * little inconsistent, though. */ if (ubi_is_module()) goto out_detach; } } err = ubiblock_init(); if (err) { pr_err("UBI error: block: cannot initialize, error %d\n", err); /* See comment above re-ubi_is_module(). */ if (ubi_is_module()) goto out_detach; } return 0; out_detach: for (k = 0; k < i; k++) if (ubi_devices[k]) { mutex_lock(&ubi_devices_mutex); ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1); mutex_unlock(&ubi_devices_mutex); } ubi_debugfs_exit(); out_slab: kmem_cache_destroy(ubi_wl_entry_slab); out_dev_unreg: misc_deregister(&ubi_ctrl_cdev); out: class_unregister(&ubi_class); pr_err("UBI error: cannot initialize UBI, error %d\n", err); return err; } late_initcall(ubi_init); static void __exit ubi_exit(void) { int i; ubiblock_exit(); for (i = 0; i < UBI_MAX_DEVICES; i++) if (ubi_devices[i]) { mutex_lock(&ubi_devices_mutex); ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1); mutex_unlock(&ubi_devices_mutex); } ubi_debugfs_exit(); kmem_cache_destroy(ubi_wl_entry_slab); misc_deregister(&ubi_ctrl_cdev); class_unregister(&ubi_class); } module_exit(ubi_exit); /** * bytes_str_to_int - convert a number of bytes string into an integer. * @str: the string to convert * * This function returns positive resulting integer in case of success and a * negative error code in case of failure. */ static int bytes_str_to_int(const char *str) { char *endp; unsigned long result; result = simple_strtoul(str, &endp, 0); if (str == endp || result >= INT_MAX) { pr_err("UBI error: incorrect bytes count: \"%s\"\n", str); return -EINVAL; } switch (*endp) { case 'G': result *= 1024; fallthrough; case 'M': result *= 1024; fallthrough; case 'K': result *= 1024; break; case '\0': break; default: pr_err("UBI error: incorrect bytes count: \"%s\"\n", str); return -EINVAL; } return result; } /** * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter. * @val: the parameter value to parse * @kp: not used * * This function returns zero in case of success and a negative error code in * case of error. */ static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp) { int i, len; struct mtd_dev_param *p; char buf[MTD_PARAM_LEN_MAX]; char *pbuf = &buf[0]; char *tokens[MTD_PARAM_MAX_COUNT], *token; if (!val) return -EINVAL; if (mtd_devs == UBI_MAX_DEVICES) { pr_err("UBI error: too many parameters, max. is %d\n", UBI_MAX_DEVICES); return -EINVAL; } len = strnlen(val, MTD_PARAM_LEN_MAX); if (len == MTD_PARAM_LEN_MAX) { pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n", val, MTD_PARAM_LEN_MAX); return -EINVAL; } if (len == 0) { pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n"); return 0; } strcpy(buf, val); /* Get rid of the final newline */ if (buf[len - 1] == '\n') buf[len - 1] = '\0'; for (i = 0; i < MTD_PARAM_MAX_COUNT; i++) tokens[i] = strsep(&pbuf, ","); if (pbuf) { pr_err("UBI error: too many arguments at \"%s\"\n", val); return -EINVAL; } p = &mtd_dev_param[mtd_devs]; strcpy(&p->name[0], tokens[0]); token = tokens[1]; if (token) { p->vid_hdr_offs = bytes_str_to_int(token); if (p->vid_hdr_offs < 0) return p->vid_hdr_offs; } token = tokens[2]; if (token) { int err = kstrtoint(token, 10, &p->max_beb_per1024); if (err) { pr_err("UBI error: bad value for max_beb_per1024 parameter: %s", token); return -EINVAL; } } token = tokens[3]; if (token) { int err = kstrtoint(token, 10, &p->ubi_num); if (err) { pr_err("UBI error: bad value for ubi_num parameter: %s", token); return -EINVAL; } } else p->ubi_num = UBI_DEV_NUM_AUTO; mtd_devs += 1; return 0; } module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400); MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=[,[,max_beb_per1024[,ubi_num]]].\n" "Multiple \"mtd\" parameters may be specified.\n" "MTD devices may be specified by their number, name, or path to the MTD character device node.\n" "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n" "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value (" __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n" "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n" "\n" "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n" "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n" "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n" "Example 4: mtd=/dev/mtd1,0,0,5 - attach MTD device /dev/mtd1 to UBI 5 and using default values for the other fields.\n" "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device)."); #ifdef CONFIG_MTD_UBI_FASTMAP module_param(fm_autoconvert, bool, 0644); MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap."); module_param(fm_debug, bool, 0); MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!"); #endif MODULE_VERSION(__stringify(UBI_VERSION)); MODULE_DESCRIPTION("UBI - Unsorted Block Images"); MODULE_AUTHOR("Artem Bityutskiy"); MODULE_LICENSE("GPL"); MODULE_IMPORT_NS(VFS_internal_I_am_really_a_filesystem_and_am_NOT_a_driver);